Exhibit 23.1 - Consent of EY

We consent to the incorporation by reference in the Registration Statement (Form S-8) of Cullen/Frost Bankers, Inc. pertaining to the 2005 Omnibus Incentive Plan, as Amended and Restated, of our reports dated February 8, 2013, with respect to the consolidated financial statements of Cullen/Frost Bankers, Inc. and the effectiveness of internal control over financial reporting of Cullen/Frost Bankers, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2012, filed with the Securities and Exchange Commission.